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This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid acid catalyst under thermal solvent‐free conditions.  相似文献   
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Russian Journal of Physical Chemistry A - Imatinib (Gleevec) is a drug that is applied to treat cancer. It inhibits the Bcr-Abl tyrosine-kinase and therefore, it can slow growth or result in...  相似文献   
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Two series of activated carbon have been prepared by chemical activation of Amygdalus Scoparia shell with phosphoric acid or zinc chloride for the removal of Pb(II) ions from aqueous solutions. Several methods were employed to characterize the active carbon produced. The surface area was calculated using the standard Brunauer-Emmet-Teller method. The microstructures of the resultant activated carbon were observed by scanning electron microscopy. The chemical composition of the surface resultant activated carbon was determined by Fourier transform infrared spectroscopy. In the batch tests, the effect of pH, initial concentration, and contact time on the adsorption were studied. The data were fitted with Langmuir and Freundlich equations to describe the equilibrium isotherms. The maximum adsorption capacity of Pb(II) on the resultant activated carbon was 36.63 mg g−1 with H3PO4 and 28.74 mg g−1 with ZnCl2. To regenerate the spent adsorbents, desorption experiments were performed using 0.25 mol L−1 HCl. Here we propose that the activated carbon produced from Amygdalus Scoparia shell is an alternative low-cost adsorbent for Pb(II) adsorption.  相似文献   
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Research on Chemical Intermediates - The surface characteristics of nanoparticles cause their influx into the environment and lead to their interaction with fungi, algae, and plants. In the present...  相似文献   
828.
In the presence of amino acids as environmentally friendly ligands, CuI‐catalyzed Sonogashira cross‐coupling of various aryl halides with phenylacetylene was conducted to afford the corresponding internal alkynes. l ‐Methionine was found to be useful for this palladium‐free and amine‐free coupling reaction. It was also found that the solvent system plays an important role in this reaction, and significantly affects the product formation and reaction rate. Sonogashira coupling of aryl iodides and aryl bromides in dimethylsulfoxide or dimethylformamide gave the coupled products in good to excellent yields. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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An efficient procedure for the preparation of 2-amino-3-cyano-4H-chromen-4-yl phosphonate derivatives via a three-component reaction of salicylaldehyde, malononitrile and trialkyl phosphites or diethyl phosphite using inexpensive and environmentally friendly imidazole as organocatalyst has been reported. Beside excellent yields and easy workup, the reaction is done in an almost neutral medium.  相似文献   
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